Apparatus for granulating powder-like material

ABSTRACT

This invention relates to methods of granulating powder-like materials and to apparatus for accomplishing these methods. A method and apparatus according to the invention are characterized in that wet lumps, formed as a result of sprinkling a layer of powder-like material with a liquid component, in their passage on the surface of said layer are periodically subjected to squeezing with the aid of pliable members arranged on a shaft in a container charged with powder-like material. This helps obtain more compact granules featuring a uniform and smooth outer surface. The present invention relates to a field of technology involving granulation of powder-like materials and, more particularly, it relates to a method of granulating such materials and to an apparatus for accomplishing this method. The invention can be utilized in chemical, metallurgical and other branches of industry. There is well known a method of granulating powder-like materials, which consists in sprinkling a layer of powder-like material with a liquid binder component in the course of a continuous agitation of said layer and in repeatedly rolling the resulting wet lumps on the surface of the layer of powder-like material. There is also known an apparatus for the realization of said method, comprising an inclined rotatable container such as cylinder provided with means for charging powder-like material thereinto, means for feeding into said container and sprinkling over the surface of a layer of powder-like material a liquid binder component, and means for discharging finished granules from the container (cf., FRG Pat. No. 881,927, class 82 a, 19/07, issued in 1949). An essential disadvantage inherent in the known method and apparatus consists in that the outer surface of granules thus obtained is markedly rough and porous. When pouring, transporting, drying and reloading products consisting of such granules, a great amount of dust is produced impairing the sanitary conditions in the course of further handling the product, much of the product being irrevocable lost as dust. An object of the present invention is to avoid these disadvantages. The invention is aimed at the solution of a technical problem of developing a method of granulating powder-like material and an apparatus for accomplishing said method that would make for producing more compact granules feating a uniform and smooth outer surface. The problem of the invention can be solved by the provision of a method of granulating powder-like materials by sprinkling a layer of powder-like material with a liquid binder component in the course of a continuous agitation of the layer and repeated rolling of the resulting wet lumps on the free surface of the layer of powder-like material, wherein, according to the present invention, the wet lumps formed as a result of sprinkling the layer of powder-like material are periodically subjected to squeezing during their passage on the free surface of said lAyer. In an apparatus for accomplishing the method of the invention, comprising a rotatably mounted container such as cylinder provided with means for charging powder-like material thereinto and with means for pulverizing inside said container the liquid binder component for sprinkling the powder-like material, according to the invention, inside said container are mounted pliable members, each made as an endless belt, secured on at least one shaft passed through the container so that the lower portion of each pliable member contacts the surface of the layer of powder-like material charged into the container. It is expedient that in the apparatus for granulating powderlike materials the shaft passed through the container be made capable of rotation in a direction opposite to that of the container rotation. This helps effect the squeezing of the wet lumps rolling on the free surface of the layer of powder-like material accompanied with the movement of the squeezing surface of the pliable members. The pliable members can be made hollow and filled with a medium such as gas, liquid or free-flowing solid material. This makes for adjustment of the degree of pliability of the members and of their pressure upon the surface of the layer of wet lumps rolling on the free surface of the layer of powder-like material. Thus, the present method of granulating powder-like materials and the apparatus for accomplishing said method, embodying the present invention, provide a successful technical solution to the above-listed problems of the invention.

United States Patent Vagm et al. [451 Aug. 8, 1972 [54] APPARATUS FOR GRANULATING [561' References (Iited POWDER-LIKE MATERIAL UNITED STATES PATENTS [72] lnventors: Alexei Alexeevich Vagin, Veniamln Nnmhevich slnlygin viktor Ivan, 1,994,718 3/ 1935 Lellep ..18/1 A ovich shibofln, Vladimir n h M 2,293,439 8/1942 Lloyd ..18/1 A rakhver, Nikolai Gflgoflevich 2,812,541 11/1957 Webster 6118/1 A sharov, a" of Dzerzhinsk U.S.S R 2,994,912 8/1961 Eades ..18/1 A 3,083,081 3/1963 Sharp et a1... .....l8/l A X [73] Assignee: Dzuzhinsky filial nanchno-issledo- 3,312,530 4/1967 Sackett ..l8/l B UX ratelskogo i konstruktorskvgo instituta Khimicheskogo instltuta Khlmiimer Examiner-Robert p e r. rcheskogo mashi-nostroenla, DzeryH0lman&Stern zhinsk, USSR.

[57] ABSTRACT Filed! 1 1970 This invention relates to methods of granulating powder-like materials and to apparatus for accom- [211 App] 90524 plishing these methods.

A method and apparatus according to the invention [30] Foreign Application Priority Data are characterized in that wet lumps, formed as a result Nov. 24, 1969 U.S.S.R. ...................1378801 of sprinkling a layer of powder-like material with a liquid component, in their passage on the surface of [52] 0.8. CI. ..425/78, 264/117, 425/222 said layer are periodically subjected to squeezing with [51] int. Cl ..B29b U112, 32% ll06 the aid of pliable members arranged on a shafi in a [58] Field of Search ....l8/2 A, 2 EM, 2 ES, 1 A, l B; Container charged witli powder-like material. This helps obtain more compact granules featuring a uniform and smooth outer surface.

1 APPARATUS FOR GRANULATING POWDER-LIKE MATERIAL The present invention relates to a field of technology involving granulation of powder-like materials and, more particularly, it relates to a method of granulating such materials and to an apparatus for accomplishing this method.

The invention can be utilized in chemical, metallurgical and other branches of industry.

There is well known a method of granulating powder-like materials, which consists in sprinkling a layer of powder-like material with a liquid binder component in the course of a continuous agitation of said layer and in repeatedly rolling the resulting wet lumps on the surface of the layer of powder-like material.

There is also known an apparatus for the realization of said method, comprising an inclined rotatable container such as cylinder provided with means for charging powder-like material thereinto, means for feeding into said container and sprinkling over the surface of a layer of powder-like material a liquid binder component, and means for discharging finished granules from the container (of, FRG Pat. No. 881,927, class 82 a, 19/07, issued in 1949).

An essential disadvantage inherent in the known method and apparatus consists in that the outer surface of granules thus obtained is markedly rough and porous. When pouring, transporting, drying and reloading products consisting of such granules, a great amount of dust is produced impairing the sanitary conditions in the course of further handling the product, much of the product being irrevocable lost as dust.

An object of the present invention is to avoid these disadvantages.

The invention is aimed at the solution of a technical problem of developing a method of granulating powder-like material and an apparatus for accomplishing said method that would make for producing more compact granules feating a uniform and smooth outer surface.

The problem of the invention can be solved by the provision of a method of granulating powder-like materials by sprinkling a layer of powder-like material with a liquid binder component in the course of a con tinuous agitation of the layer and repeated rolling of the resulting wet lumps on the free surface of the layer of powder-like material, wherein, according to the present invention, the wet lumps formed as a result of sprinkling the layer of powder-like material are periodically subjected to squeezing during their passage on the free surface of said layer.

In an apparatus for accomplishing the method of the invention, comprising a rotatably mounted container such as cylinder provided with means for charging powder-like material thereinto and with means for pulverizing inside said container the liquid binder component for sprinkling the powder-like material, according to the invention, inside said container are mounted pliable members, each made as an endless belt, secured on at least one shaft passed through the container so that the lower portion of each pliable member contacts the surface of the layer of powder-like material charged into the container.

It is expedient that in the apparatus for granulating powder-like materials the shaft passed through the container be made capable of rotation in a direction opposite to that of the container rotation. This helps effect the squeezing of the wet lumps rolling on the free surface of the layer of powder-like material accompanied with the movement of the squeezing surface of the pliable members.

The pliable members can be made hollow and filled with a medium such as gas, liquid or free-flowing solid material.

This makes for adjustment of the degree of pliability of the members and of their pressure upon the surface of the layer of wet lumps rolling on the free surface of the layer of powder-like material.

Thus, the present method of granulating powder-like materials and the apparatus for accomplishing said method, embodying the present invention, provide a successful technical solution to the above-listed problems of the invention.

This invention will be better understood upon considering the following detailed description of the present method of granulating powder-like materials and apparatus for accomplishing same, reference being had to the accompanying drawings in which:

FIG. 1 is a general view of an apparatus embodying the present invention; and

HO. 2 is a section taken on line llll of FIG. 1.

The present method of granulating powder-like materials will become apparent upon considering a preferred embodiment of an apparatus for accomplishing said method, as illustrated in F I08. 1 and 2.

The method of granulating powder-like materials, according to the invention, consists in the following.

Referring now to FIG. 1, initial powder-like materials is continuously fed via spout l to a container, in particular, cylinder 2, and the layer of charged material is sprinkled on the surface with a liquid binder component that is also continuously delivered via pipeline 3 and pulverized in fine drops with the aid of pulverizers 4. Small wet lumps formed on the layer surface during the rotation of the cylinder 2 from a drive 5 are continuously agitated together with powder-like material and with each turn of the cylinder 2, pass a part of their path inside the layer and a part of the path on the surface of said layer. When passing on the surface of the layer, the lumps are subjected to squeezing by pliable members 6 (FIGS. 1, 2) rotating together with a shaft 7 in a direction opposite to that of the rotation of the cylinder 2. The pliable members 6 can be made continuous over the length of the cylinder 2 or they can be composed of separate sections arranged longitudinally and somewhat spaced from each other. Each of said members can be made hollow in cross section. In order to provide a possibility of 189 adjusting the degree of pliability of the pliable members depending upon the properties of the material being granulated, the moisture content of the latter and the required size of granules, the inner spaces of the pliable members can be filled with gas, liquid or free-flowing solid material such as shots.

Attached to the inner wall of the cylinder 2 are longitudinal extending flanges 8 unifonnly distributed over the length and circumference of the cylinder 2 which are adapted to scoop the powder-like material from the inside of the layer, when in their lower position, and to pour said material onto the wet lumps rolling under the pliable members 6, when in their extreme upper position. This helps prevent the mass of moist product from adhering to the outer surface of the pliable members 6 and to intensify the rolling of the powder-like product onto the wet lumps, thereby increasing the efficiency of the process.

Referring to F IG. 2, the inner surface of the cylinder 2 can be covered with longitudinally extending rubber strips 9 attached to the wall of the cylinder 2 with their long edges. When in their top position during the rotation of the cylinder 2, the strips 9 cave in, as a result of which the crust of wet mass adhered thereto breaks up and comes off.

As illustrated in H6. 2, the pliable members 6 are made in the form of a thin endless belt loose-fitted on an intermediate cylinder 10 secured on the shaft 7. When so doing, the lower portion of the pliable members 6 sags under the effect of gravity and contacts the layer of wet lumps rolling on the surface of the layer of powder-like material. The pliable members 6, however, can be set directly on one or more stationary axles parallel to the axis of the shaft 7 and secured to said shaft, for example, by means of brackets provided with bearings adapted for the passage therethrough of the shaft (not show in the drawings).

The cylinder 2 is also provided with a discharge chamber ll (FIG. 1), a rimmed toothed wheel 12 connected with the drive 5, and binding bands 13, and is mounted with a slight inclination towards its discharge end on bearing 14 and thrust l5 rollers,

The shaft 7 is rotated by a drive 16 mounted on a frame 17.

In the preferred embodiment of the apparatus described hereinabove the cylinder 2 is provided with the flanges 8 and the longitudinally extending strips 9, however, the use of said elements for accomplishing the method according to the invention is not imperatlve.

Also, in the embodiment described herein the shaft 7 is made capable of rotation in a direction opposite to that of the cylinder rotation. However, said shaft can rotate in the other direction or be loose-mounted in bearings provided on the outer side of the cylinder (not show in the drawings).

We claim:

1. An apparatus for granulating powder-like materials, comprising: a rotatably mounted container, made preferably as a cylinder; means for charging powderlike material into said container; means for pulverizing inside said container at liquid binder component for sprinkling powder-like material therewith; at least one shaft passing through said container; pliable members, each made as an endless belt, said pliable members being secured on said at least one shaft so that the lower portion of each of said pliable members contacts the surface of the layer of powder-like material charged into said container.

2. An apparatus as set forth in claim I, wherein said shaft passing through said container is made capable of rotation in a direction opposite to that of rotation of said container.

3. An apparatus as set forth in claim 1, wherein said pliable members are made hollow and filled with a medium with means for adjusting the degree of their pliability and of their pressure upon the surface of the l r f de -lik mate 'al Kn pgara tus s set drth in claim 3, wherein a gas is used as the medium adapted to fill the spaces of said pliable members.

5. An apparatus as set forth in claim 3, wherein a liquid is used as the medium adapted to fill the spaces of said pliable members.

6. An apparatus as set forth in claim 3, wherein a free-flowing solid material is used as the medium adapted to fill the spaces of said pliable members. 

1. An apparatus for granulating powder-like materials, comprising: a rotatably mounted container, made preferably as a cylinder; means for charging powder-like material into said container; means for pulverizing inside said container a liquid binder component for sprinkling powder-like material therewith; at least one shaft passing through said container; pliable members, each made as an endless belt, said pliable members being secured on said at least one shaft so that the lower portion of each of said pliable members contacts the surface of the layer of powder-like material charged into said container.
 2. An apparatus as set forth in claim 1, wherein said shaft passing through said container is made capable of rotation in a direction opposite to that of rotation of said container.
 3. An apparatus as set forth in claim 1, wherein said pliable members are made hollow and filled with a medium with means for adjusting the degree of their pliability and of their pressure upon the surface of the layer of powder-like material.
 4. An apparatus as set forth in claim 3, wherein a gas is used as the medium adapted to fill the spaces of said pliable members.
 5. An apparatus as set forth in claim 3, wherein a liquid is used as the medium adapted to fill the spaces of said pliable members.
 6. An apparatus as set forth in claim 3, wherein a free-flowing solid material is used as the medium adapted to fill the spaces of said pliable members. 